The political world is still split between those who still think its September 10th and those of us who have passed onto September 12th (ok, admittedly, some of you guys are still living on November 8, 1989 or, more bizarrely, wish you were). You can make a relatively convincing case that September 11th wasn't "special" - after all, American assets and citizens had been targetted through the 1980s and 1990s (in Africa, Saudi Arabia, Lebanon and, of course, New York). And America slept. Sure, Clinton bombed a few countries at random when he was being impeached, but terrorism and national security weren't the defining issues of American politics. Now, they are.

If you're unkind, you might say this is unreasonable of them. This is ridiculous. Let us remember what happened on 9/11/01 and put it in perspective. 3000 people of all nationalities died in the Twin Towers, symbols of American culture, prosperity and peaceful commerce. This is what people usually focus on when they discuss the day, but let's remember what else was hit - the Pentagon. The epicenter of the American military machine, the hub of American global power was attacked. And it was vulnerable. About 125 of America's military and intellectual elite died there. Thousands of people of all nationalities died in the Towers and hundreds of firefighters died trying to save them.

The people who did this were not members of a national army, they were not a loose, ragged group of nutcases, they were members of a well-organised, tightly-knit set of international terrorists who received money and at least tacit approval if not active help from a number of regimes in the Middle East, some of which were supposedly America's friends. This was a wake-up call. At the most basic level, no American politician could afford to ignore the possibility of jetliners crashing into American skyscrapers. Something had to be done. And so, after a month of careful deliberation, President Bush invaded Afghanistan with a broad coalition.

But I digress. This isn't a history lesson - this is reflections on the future. I'll be brief about the past. In two years, America - first with help, then abandoned by the comity of nations it was and always has protected, often from each other - has liberated fifty million people and destroyed two despicable regimes, the Taliban and the authoritarian government of Saddam Hussein. All this was accomplished at the cost of less than 300 American lives. They were two of the most humane military campaigns ever fought. Yes, civilians died - perhaps 10,000 in Iraq (one wonders how many were slaughtered by their countrymen during the campaign, never mind the numbers the regime has killed in its years of power). The battle for Iraq was so humane that now American lives are being lost because large swathes of the country weren't pacified.

Our enemies understand strength and have only contempt for weakness. Weakness is what was displayed to them until 9/11/01 - not any more. The al Qaeda leadership is in retreat for the first time in decades, pushed there in part by America's "friends" such as Pakistan and Saudi Arabia, now forced to make good on their promises. Iraq is the new front line in the War on Terror, as jihadists pour in from Syria and Iran to try and destabilise Iraq and prevent the spread of democracy, freedom and liberalism throughout the Middle East. Make no mistake, this is a war of opposing ideologies, and one we must win. We have seen where appeasement got us, we have paid the price for doing nothing - now our enemies must pay the price for their audacity.

If the war is to be won, it must be waged with unity and without compromise. For a brief while, this looked possible, as the American nation committed to Afghanistan as it had committed to nothing since World War II. But the reaction of the Left to the war on Iraq shows that they fundamentally do not understand what this war is all about, that this is a generational war, a war as important as World War II and as important as the Cold War. Did America merely attack its aggressor after Pearl Harbor? No, it attacked authoritarian Europe in all its guises, from Italy to Germany.

The so-called "intelligentsia" across Europe and in America wants to argue about fifteen words in Bush's State of the Union address, about who said what to whom in the run up to the publishing of a Downing Street Dossier. Those who wish to use this as political capital are despicable and those who wish to hilight it as a sign of abuse are best described as complacent. Today, I saw an advertisement for tonight's evening news, in which the presenter shockingly "revealed" that "spy chiefs" told Tony Blair that the invasion of Iraq might facilitate the proliferation of WMD. This blows my mind. Does anyone seriously think this was not taken into account - that the pros and cons of the invasion were not weighed carefully? Was it not obvious to any fool that the chaos of wartime Iraq might make it easy for WMD to slip away? Do we really need to be told this in a "shock report"?

But these people have already forgotten. They'd forgotten the Khobar Towers, the Iranian embassy, the World Trade Centre in 1993, the U.S.S Cole, Dar es Salaam and Nairobi by 2001. They forgot the good work done by the United States in Kosovo, Bosnia, Somalia and the criminal negligence of the "superior" Europeans in Rwanda. And now, only two years later, they've forgotten 9/11/01 already. So go on. You forget. Thanks to the diligence and determination of those who can't, you'll hopefully be free to do so for a long time yet. American blood and treasure brought a fragile peace to Western Europe for fifty years, and they still live in it. But two years ago today, that peace was broken on American soil. If you want to understand the next half century, you'll do well not to forget that.